Patch 5.2.0g is the unofficial name for the patch build 16733 that came out about 2 days after the unofficially named "Patch 5.2.0f" build 16716. There is no info on this patch build and there has been no official acknowledgement of the release of this patch build. This client could also correspond to the March 19, 2013 slate of hotfixes. It isn't clear why a client patch is needed.